For the jet flow impacting on the launch device when solid rockets flying away from the launching device,the computational fluid mechanics and experimental measurement are used to simulate and measure the impact load of the jet flow.The 3-D viscous turbulent flow model and the dynamic grid technique are carried out to simulate the rocket launch process and the laws of flow field in the process of impact,the gas pressure distribution on the surface and the change courses of pressure-time are obtained.The experiment scheme is designed according to the results of numerical analysis,and the pressure-time relationship of measuring points is obtained by experimental measurement.The comparision of the numerical and experimental results shows that their errors of the peak pressure are about 18% and their pressure-time change courses are consistent.The numerical analysis method in this paper can be used in the simulation of the gas impact field of the solid rocket jet flow.